HANTHA WADD Y 27
and the Pazundaung stream from the north-east and north, and thence
flows southwards under the name of the Rangoon river into the Gulf
of Martaban. The District is further intersected by numerous tidal
creeks, all navigable by country boats and many by river steamers.
The most important of these are the Thatkutpin or Bassein creek,
which connects the Rangoon river with the To, and thus with the main
stream of the Irrawaddy ; the Panhlaing, which during the rains, when
the water is high, takes the place of the Bassein creek as the most
direct route to the Irrawaddy; the Bawle river, which divides Hantha-
waddy from the adjoining District of Ma-ubin; and the Hmawwun,
which taps the rich rice-fields of the Kyauktan subdivision.
The plains of the delta are composed of homogeneous post-Tertiary
alluvium resting on a bed of water-worn gravel, which is often found
at a depth of less than 250 feet and is a good water-bearing stratum.
Along the skirts of the Pegu Yoma a broad bed of sandy deposit
occurs; and laterite, which is largely used for road-metalling, is found
in many of the lower hills, mixed with red alluvial clay. Occasionally
partially rolled pieces of fossil wood are met with. The Yoma itself
is formed of beds of the Pegu group, of miocene age.
The coast-line is fringed with dense low mangrove jungle, covered
regularly by the tide, and characterized specially by species of
Bruguiera and Rhizophora. Behind these forests and along the
borders of the tidal channels are the tidal forests, the most character-
istic trees of which are Sonneratia apetala and Avicennia tomentosa.
These forests average 40 to 50 feet in height, and have a thick shrubby
growth, similar to that of the mangrove forests. Nipa fruticans and
Pandanus foetZdus form dense bushes, and Phoenix paludosa is very
common. Creepers and climbers abound, including Acanthus volubilis,
Flagellaria indica, &c. Behind this zone are either open evergreen
tropical or low deciduous forests. Among the former are found
Parashorea stellata, Pentace burmannica, Albizzza lucida, Lagerstroemia
tomentosa, and Dillenia parvifora, and many varieties of shrubs and
climbers. The low deciduous forests contain Dillenia pulcherrima,
Shorea leucabotrya, Pentacme siamensis, Melanorrhoea usitata, Xylia
dolabriforsnis, Lagerstroemia macrocarpa, Albizzia lucida, and Strychnos
Nix-vomica. The undergrowth is usually composed of scanty andro-
pogonous grasses. The savannah forests are distinguished by the great
growth of elephant-grasses, among which the trees grow up apart from
one another; they include Butea frondosa, Ficus fistulosa, Terminalia
crenata, Dalbergia cultrata, Dalbergia purpurea, Lagerstroemia Flos
Reg-inae, and Strychnos Nux-vomica.
In the Yoma, elephants, bison, tsine or hsaing (Bos sondaicus), and
various kinds of deer are common; rhinoceros are rare. There are
indications that tigers and leopards are increasing in consequence